Image readers for reading an image on a document are used by themselves as an image scanner, or used in combination with an image forming device as a multifunction apparatus.
An image reader is provided, for example, with an image sensor and a document conveying path extending past the image sensor. The conveying path is formed by a plurality of rollers for conveying the document, guide surfaces for guiding the document, and the like members. While the document is conveyed along the document conveying path, the document comes to face the image sensor. In this instance, light is cast from the image sensor onto the document. Then, the reflected light from the document is received by the image sensor, whereby reading of the image formed on the document is achieved.
Among such image readers, there are those in which a document may be conveyed through either of two document conveying path, and either of the two document conveying path is selectively established by movable of a cover provided in a main body of the device. According to one conventional configuration, a U-shaped document conveying path is formed by the inner surface of the cover when the cover is in a closed state. When the cover is in an open state, on the other hand, a certain part of the U-shaped document conveying path is opened, whereby a straight document conveying path is formed. In the case of a document with comparatively low stiffness, the cover is kept closed and the document is conveyed through the U-shaped document conveying path, whereby reading of the image on the document is achieved. In the case of a document with comparatively high stiffness such as a thick document, on the other hand, the cover is opened and the document is reasonably conveyed through the straight document conveying path, whereby reading of the image on the document is realized.